The energy released during the combustion (digestion) of nutrients in the organism is measured in kilojoules (kJ) and referred to as the physiological calorific value. This can be used to calculate the energy content of nutrients, which is important for certain diets, for example. Examples: 1 g carbohydrates = 17.2 kJ, 1 g fats = 38.9 kJ. The evaluation of combustion is called quantitative nutritional value. However, the outdated term kilocalorie is still commonly used. The conversion:
- Kilocalorie: 1 kcal = 4.1868 kJ
- Kilojoule: 1 kJ = 0.2388 kcal
- Watt hour: 1 kcal = 1.163 Wh
Calorie values
After fat,alcohol contains the most calories, almost twice as much as sugar. Wine has a relatively high calorific value or large proportion of calories, namely around 500 to 600 Kcal per 0.75 litre bottle or 85 to 100 Kcal per glass, which is mainly due to the alcohol content. For a bottle of brandy with 38% alcohol by volume, this is around three times as much. Alcohol is a high source of energy, 7 Kcal per gram, which is an average of around 90 Kcal per eighth of wine.
One litre of wine is equivalent to 0.8 kg of potatoes, 1 litre of whole milk, 10 eggs, 100 g of butter, 400 g of rye bread or three rolls with 50 g of Leberkäse. With light work, a person needs around 2,500 Kcal a day, with heavy work around 4,000 Kcal. The US drinks multinational Diageo started to list the "big four" on the labels of some wines as early as 2004. Chardonnay, for example: 124 calories, less than 1 g protein, 3 g carbohydrates, 0 g fat per 5-ounce serving (0.15 litres).
Nutritional labelling
Under European law, pre-packaged foods placed on the market in the EU must be labelled with consumer information about their energy and nutrient content. This "nutrition declaration" must appear directly on the packaging or on a label attached to it. The declaration of the following nutrients as part of the nutrition declaration is voluntary: monounsaturated fatty acids, polyunsaturated fatty acids, polyhydric alcohols, starch, fibre, legally permitted vitamins or minerals. The substances that must be labelled are listed below.
Labelling obligation for wine from 2023
According to the EU regulation, certain alcoholic products will be treated as foodstuffs from 8 December 2023. These are wines, sparkling wines, semi-sparkling wines, liqueur wines, fruit wines, partially fermented grape musts (e.g. Federweißer, Sturm), flavoured wines (e.g. mulled wine) and cocktails containing wine. These must be labelled with a list of nutritional values and ingredients. All wine labels must include detailed information on nutritional values, additives and allergens.
This labelling obligation applies not only to bottles, but also to price lists, online shops and other forms of ordering. The information on the label must be in tabular form. With an "e-label" (QR code), the complete nutrition declaration and list of ingredients can also be provided digitally. However, calorific value information and allergen labelling must be shown directly on the wine label despite the QR code.
Nutritional values
The nutrition declaration includes information on calorific value, fat, of which saturated fatty acids, carbohydrates, of which sugar, protein and salt (referred to as the "big eight" together with dietary fibre). The calorific value in kilojoules (kJ) and kilocalories (kcal) is calculated from the parameters alcohol content, residual sugar content, acidity and glycerine (or sorbitol in the case of fruit wines). The calorific value must be indicated on the label with the notification for the quality wine test number. For wines without a quality wine test number, this can be calculated by the producer using a formula.
The value for carbohydrates is calculated from the residual sugar plus glycerine content of the wine (according to the EU definition, the term carbohydrates also includes polyhydric alcohols). The glycerol content can be assumed to be 8 g/l for wines (with the exception of Prädikat wines). For Prädikat wines, the glycerol content can be found in the test number certificate.
Fat, saturated fatty acids, protein and salt are contained in wine in negligible quantities. It is therefore generally not necessary to analyse these values. Alternatively, the statement "Contains negligible amounts of fat, saturated fatty acids, protein and salt" is permitted below the table (see bottom left of the label).
The nutritional information always refers to 100 ml. The calorific value in kJ and kcal as well as the carbohydrates and sugars over 10 g per 100 ml are stated without decimals. The values of fat, of which saturated fatty acids, carbohydrates, of which sugars and proteins, each less than 10 g per 10 ml, are given to the nearest 0.1 g; in the case of table salt, however, to the nearest 0.01 g.
The permissible tolerances are harmonised in the EU. Accordingly, a tolerance of 2 g/100 ml (equivalent to 20 g/l) is permitted for the declaration of sugar/carbohydrates for wines below 100 g/l (i.e. generally all wines except noble sweet wines). For noble sweet wines with more than 100 g/l sugar, ± 20% deviations in the indication of carbohydrates/sugar are tolerable. No EU-wide harmonised tolerance is specified for the calorific value; a certain fluctuation range is accepted.
Ingredients and allergens
In addition to the nutritional values, all ingredients (processing aids) that are necessary for the production of a wine and are not completely consumed or removed must also be listed. Substances for deacidification do not usually remain in the end product and therefore do not have to be mentioned in the list of ingredients. The list must begin with the word "Ingredients:", followed by the list of ingredients used in descending order of quantity (mass). The list always begins with the term "grapes" or "grape must" (if not already covered). In the case of enrichment, the term "sugar" usually follows. Allergens must be labelled and highlighted in the list of ingredients.
Examples of ingredient lists
The list of ingredients for a typical winemaking process could be as follows (starting with "Ingredients:"):
Red wine: grapes, sugar, concentrated grape must, stabilisers: gum arabic, metatartaric acid; antioxidants: sulphur dioxide; packaged in a modified atmosphere ( nitrogen was used as an inert gas during bottling )
White wine: grapes, sugar, concentrated grape must; stabilisers: metatartaric acid and/or carboxymethylcellulose; acidity regulators: Tartaric acid; carbon dioxide; antioxidants: sulphur dioxide, L-ascorbic acid; packaged under modified atmosphere
Further information
For more information on this topic, see also labelling, as well as a complete list of relevant terms under wine law.
Potato: by Freud - Own work, CC BY-SA 4.0, Link
Wine bottle: by Clker-Free-Vector-Images on Pixabay
Source and labels: Verena Klöckl, BA MA lkonline - Burgenland Chamber of Agriculture
Source: Austrian Chamber of Commerce
